Search results
Results from the WOW.Com Content Network
Buck–boost transformers can be used to power low voltage circuits including control, lighting circuits, or applications that require 12, 16, 24, 32 or 48 volts, consistent with the design's secondaries. The transformer is connected as an isolating transformer and the nameplate kVA rating is the transformer’s capacity. [2]
Some large European appliances may be powered by three-phase power, such as electric stoves and clothes dryers. A ground connection is normally provided for the customer's system as well as for the equipment owned by the utility. The purpose of connecting the customer's system to ground is to limit the voltage that may develop if high voltage ...
The line to neutral voltage is half the line-to-line voltage. Lighting and small appliances may be connected between a line wire and the neutral. Higher-power appliances, such as cooking equipment, space heating, water heaters, clothes dryers, air conditioners and electric vehicle charging equipment, are connected to the two line conductors.
Distribution transformers typically have ratings less than 200 kVA, [3] although some national standards allow units up to 5000 kVA to be described as distribution transformers. Since distribution transformers are energized 24 hours a day (even when they don't carry any load), reducing iron losses is vital in their design.
A leakage transformer, also called a stray-field transformer, has a significantly higher leakage inductance than other transformers, sometimes increased by a magnetic bypass or shunt in its core between primary and secondary, which is sometimes adjustable with a set screw. This provides a transformer with an inherent current limitation due to ...
The transformers are usually rated at 5 kVA, 10 kVA, and 25 kVA. The load densities are usually below 0.5 kVA per kilometer (0.8 kVA per mile) of line. Any single customer's maximum demand will typically be less than 3.5 kVA, but larger loads up to the capacity of the distribution transformer can also be supplied.
Pad-mounted transformers are made in power ratings from around 15 to around 5000 kVA and often include built-in fuses and switches. Primary power cables may be connected with elbow connectors, which can be operated when energized using a hot stick and allows for flexibility in repair and maintenance.
By choosing the base quantities in this manner, the transformer can be effectively removed from the circuit as described above. For example: Take a transformer that is rated at 10 kVA and 240/100 V. The secondary side has an impedance equal to 1∠0° Ω. The base impedance on the secondary side is equal to: